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51.
52.
Birgit Palm Jürgen G. Heinrich Joachim Reuer 《International Journal of Applied Ceramic Technology》2010,7(2):226-234
The essential influences of 15 parameters on defects (cracks and bubbles) during production of tableware have been studied with 16 experimental progressions using a L16(215) experimental design by G. Taguchi. Evaluation (analysis of means and analysis of variance) indicated that in this production liter weight, drying time, moisture before biscuit firing, and position in the biscuit-firing kiln have a significant influence on cracks. Concerning bubbles, parameters with an influence are liter weight, gate system, mold material, and moisture content before glost firing. Rejects of the article used in the experiments were reduced from 2.44% to 2.27% with respect to cracks and from 6.22% to 0% with respect to bubbles. 相似文献
53.
Computational probabilistic noninterference 总被引:1,自引:0,他引:1
Michael?BackesEmail author Birgit?Pfitzmann 《International Journal of Information Security》2004,3(1):42-60
Information flow and noninterference are popular concepts for expressing confidentiality and integrity properties. We present the first general definition of probabilistic noninterference in reactive systems that includes a computational case. This case is essential for coping with real cryptography since noninterference properties can usually only be guaranteed if the underlying cryptographic primitives have not been broken. This might happen, but only with negligible probability. We show that our noninterference definition is maintained under simulatability, the notion of secure implementation of modern cryptography. This allows secure composition of systems and yields a general strategy for including cryptographic primitives in information-flow proofs. As an example we study a cryptographic firewall guarding two honest users from their environment. 相似文献
54.
In this paper equivalent conditions for exact observability of diagonal systems with a finite-dimensional output operator are given. One of these equivalent conditions is the conjecture of Russell and Weiss (SIAM J. Control Opt. 32(1) (1994) 1–23). The other conditions are in terms of the eigenvalues and the Lyapunov solutions of finite-dimensional subsystems. 相似文献
55.
Systems of economic ratios are very important in the field of operative controlling. Functional equations of economic quantities may be analyzed by comparing actual current values of these variables with planned values or values of a previous period using methods of deviation analysis. In this paper different methods of deviation analysis are compared. They are based on conditions, which should be satisfied by methods used to determine the effects on a depending quantity caused by the change of its components. In some aspects these conditions are different from conditions for methods of deviation analysis used in cost accounting. Based on an approximation of the temporal change of economic quantities a new method of deviation analysis is developed. This concept satisfies all conditions formulated at the beginning of the paper. 相似文献
56.
Herschbach Peter; Duran Gabriele; Waadt Sabine; Zettler Angela; Amm Christoph; Marten-Mittag Birgit; Strian Friedrich 《Canadian Metallurgical Quarterly》1997,16(2):171
This study reports the psychometric properties of a 45-item diabetes-specific questionnaire, the Questionnaire on Stress in Patients with Diabetes—Revised (QSD-R), a modified and shortened version of the QSD (G. Duran et al; see record 1996-18805-001). The QSD-R was filled out by 1,930 individuals with insulin-dependent diabetes mellitus and noninsulin-dependent diabetes mellitus. Eight consistent scales were identified (values of Cronbach's α: .69–.81). The test-retest reliability for the total score after a 5-week interval was rtt?=?.63. The results provide evidence for the reliability and validity of this instrument. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
57.
Susanne Rinn Birgit Stallmeyer Alexandra Pinggera Michael F. Netter Lina A. Matschke Sven Dittmann Uwe Kirchhefer Ulrich Neudorf Joachim Opp Jrg Striessnig Niels Decher Eric Schulze-Bahr 《International journal of molecular sciences》2022,23(22)
Cav1.3 voltage-gated L-type calcium channels (LTCCs) are involved in cardiac pacemaking, hearing and hormone secretion, but are also expressed postsynaptically in neurons. So far, homozygous loss of function mutations in CACNA1D encoding the Cav1.3 α1-subunit are described in congenital sinus node dysfunction and deafness. In addition, germline mutations in CACNA1D have been linked to neurodevelopmental syndromes including epileptic seizures, autism, intellectual disability and primary hyperaldosteronism. Here, a three-generation family with a syndromal phenotype of sinus node dysfunction, idiopathic epilepsy and attention deficit hyperactivity disorder (ADHD) is investigated. Whole genome sequencing and functional heterologous expression studies were used to identify the disease-causing mechanisms in this novel syndromal disorder. We identified a heterozygous non-synonymous variant (p.Arg930His) in the CACNA1D gene that cosegregated with the combined clinical phenotype in an autosomal dominant manner. Functional heterologous expression studies showed that the CACNA1D variant induces isoform-specific alterations of Cav1.3 channel gating: a gain of ion channel function was observed in the brain-specific short CACNA1D isoform (Cav1.3S), whereas a loss of ion channel function was seen in the long (Cav1.3L) isoform. The combined gain-of-function (GOF) and loss-of-function (LOF) induced by the R930H variant are likely to be associated with the rare combined clinical and syndromal phenotypes in the family. The GOF in the Cav1.3S variant with high neuronal expression is likely to result in epilepsy, whereas the LOF in the long Cav1.3L variant results in sinus node dysfunction. 相似文献
58.
Image-guided, computer-assisted surgery systems require a common reference between the preoperative image data and the corresponding patient pathology. Therefore, the problem of an accurate and reliable 3-D patient registration and referencing has to be solved. Considering that during image data acquisition patient misalignment and movement can arise in three dimensions, an automatic image registration method must be based on a three-dimensional approach. The method presented in this paper provides accurate 3-D patient registration for correction of these movement errors during data acquisition and active patient referencing to update the position of the head during surgery. Experimental data concerning the accuracy of repeated positionings of our patient registration and reference system demonstrated a high degree of accuracy with mean spatial errors of 0.82 mm ± 0.31 mm in a plastic skull and 1.56 ± 0.76 mm in patients, respectively. Results suggest that non-invasive 3-D patient registration for image-guided surgery may be a precise and useful method for computer-assisted identification of anatomical structures. 相似文献
59.
The new classification system for the reaction to fire performance of building products in Europe has been applied to five different product families of wood: Wood-based panels, Structural timber, Glued laminated timber, Solid wood panelling and cladding and Wood flooring as being ‘products with known and stable fire performance’. The European classification system includes two sub-systems, one main system for all construction products except floorings and the other for flooring products. Wood properties such as density, thickness, joints and types of end use application including different substrates have been studied thoroughly and are included in the classification. Most wood products fall in classes D-s2, d0 or Dfl-s1 (for floorings). Testing has been performed according to EN 13823 (2002) SBI- Single Burning Item test, EN ISO 9239-1 (2002) Radiant panel test, and EN ISO 11925-2 (2002) Small flame test. In all, more than one hundred wood products in different end use applications have been studied. Clear relationships between the main Euroclass fire performance parameters and product parameters (such as density and thickness) have been demonstrated. Tables with reaction to fire classification of different wood products and end use applications have been developed, approved by the European Commission and published in their Official Journal. This procedure is ongoing with further official decisions to be published. 相似文献
60.
Mokros Andreas; Menner Birgit; Eisenbarth Hedwig; Alpers Georg W.; Lange Klaus W.; Osterheider Michael 《Canadian Metallurgical Quarterly》2008,117(2):406
Maladaptive social behavior is one of the defining characteristics of psychopathic personality disorder. Nevertheless, maladaptive social behavior has only rarely been observed among psychopaths in experimentally controlled situations. The authors assessed the behavior of criminal psychopaths from high-security psychiatric hospitals in a computer simulation of a social dilemma situation. The psychopaths showed a markedly higher proneness to competitive (i.e., noncooperative) behavior than did healthy adults from the general population. The odds ratio between defection and being a psychopath was estimated at 7.86 in the sample. The probability to choose selfish instead of cooperative behavior was significantly linked to the following subscales of the Psychopathy Personality Inventory-Revised (S. O. Lilienfeld & M. R. Widows, 2005): rebellious nonconformity, Machiavellian egocentricity, and the total score. On average, the psychopathic participants accumulated higher gain and more strongly exploited their counterpart than did the healthy participants. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献